Should you enable HTTP/2?

Question

Nginx

Hello!
There are a thousand questions about the race for speed and safety.
1. It is worth turning on http/2 now, what rake do you expect?
2. What browsers support it?
3. How long to wait for full support?
4. Will users with older browsers be able to use 1.1 by enabling http2?
5. Really cool and convenient technology?

Answer 1

Chrome supports HTTP/2. Only HTTP/2 over TLS is supported.
Chrome for iOS supports HTTP/2.
Firefox has supported HTTP/2 since version 36. Experimental support for HTTP/2 was originally provided in version 34. Only HTTP/2 over TLS mode is supported.
Internet Explorer has supported HTTP/2 since version 11, but only for Windows 10. Only HTTP/2 over TLS mode is supported.
Microsoft Edge supports HTTP/2.
Opera supports HTTP/2.
Safari 9 supports HTTP/2.
source wikipedia
Conclusion: do not rush. ;)

Answer 2

caniuse.com/#search=http2 = 67.89%

Answer 3

Google and Yandex are still experiencing difficulties with indexing.
If indexing is important to you, don't rush it yet.